Missing Blender Prefs folder on other Mac user account
Never mind.
I thought that a Blender folder automatically got created upon the first launch of Blender under that account.
But it turns out that you need to save some preferences of some sort in order for that folder to be created. Once you do that the folder appears, and then just swap out the 2.92 folder for the one containing the preferences your desire to copy over.
Or you could just create the ~/Library/Application Support/Blender/ folder yourself. There is no need to rely on the app to do it.
Pretty simple stuff. My mistake was just based on the flawed assumption that it gets created on first launch. But it's actually on first prefs save.
Please move along, nothing to see here...